Water level control for boilers



April 20,1937. ERNST 2,077,679

WATER LEVEL CONTROL FOR BOILERS Filed Jan. 15, 1934 INV ENT OR. 6901 0 51285,

M 13% ATTORNEY.

Patented Apr. 20, 1937 UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to liquid level controls and indicators, and has particular reference to devices intended for high pressure steam boilers.

One object of the invention is to provide a device of this character having control elements such as electrodes mounted in an improved manner in connection with the water column of a boiler but externally thereof.

Another object of the invention is the provision of a device of the nature set forth having a control element or electrode and a valve having improved coaction therewith, whereby removal of the electrode will result in closing of the valve.

Another object of the invention is to provide a device as set forth having improved means whereby the electrodes may be cleaned by a flow therealong.

Another object of the invention is to provide an improved electrode mounting, and an improved combined packing and insulating arrangement.

Essentially the invention aims to avoid the necessity of using gage glasses, which are subject to numerous drawbacks, or floats which require movable mechanism, and to provide a simple, stationary, rugged, entirely safe and reliable device, which can also control the liquid level in any container or boiler.

Other objects and advantages of the invention will become apparent as the specification proceeds.

With the aforesaid objects in view, the invention consists in the novel combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subijoined claims, and illustrated in the annexed drawing, wherein like parts are designated by the same reference characters throughout the several views.

In the drawing:

Figure 1 is a view in front elevation showing a device embodying the invention.

Fig. 2 is a fragmentary enlarged sectional view taken on the broken line 2-2 of Fig. 1.

Fig. 3 is a sectional view of an electrode and mounting therefor.

The advantages of the invention as here outlined are best realized when all of its features and instrumentalities are combined in one and 5 the same structure, but, useful devices may be produced embodying less than the whole.

It will be obvious to those skilled in the art to which the invention appertains, that the same may be incorporated in several different constructions. The accompanying drawing, therefore, is submitted merely as showing the preferred exemplification of the invention.

Referring in detail to the drawing, Ill denotes a device embodying the invention. The same may include a liquid container or high pressure 5 boiler ll having a water column l2 which may consist of a section of ordinary pipe having vertically spaced tubes l3 secured or welded thereto and flanged at M to the boiler. The pipe l2 may be closed as by upper and lower caps 15. In this 10 inexpensive water column, the liquid level is free and is the same as in the boiler.

Connected to the water column 12 at vertically spaced points are a plurality of devices l6 and II which may be exact duplicates of each 15 other. Each device may have a one piece valve casing [8 of generally cylindrical form and having a tubular extension [9 connected by a union fitting 20 with the water column. Said valve casing I8 may also have an integral or 20 union connected casing extension 2| embodying a try cook or blow off valve of any suitable type, operative by a cross bar 22 on the stem 23 to control a fluid discharge through the port 24.

Within the valve casing I8 is a central cylin- 25 drical chamber 25 communicating with a passage 26 in the tubular extension [9 said passage having preferably a constriction as at 21, which may also afford a valve seat 28 for a ball valve 29. The latter is movable along the passage 26, is 30 retained therein by a cross pin 30, and is adapted to close the passage by engaging the seat 28 under the pressure of fluid from the boiler. Also communicating with the chamber 25 is a connection at 3| leading to the try cock 2|. 5

Interconnecting the devices I6, I! or specifically the valve casings I 8 is an indicating or liquid level control means 53 which may include tubular means having movable or swing joint connection as at 54 with the valve casings at 40 right angles to the axes of connection thereof with the water column, whereby upon turning the valve casings, the means 53 may be raised or lowered as a unit to set the same at the time when the invention is being installed. 45

The swing connections 54 are duplicates of each other and each may include a series of three elbow fittings 55, 56, 51. Thus the elbow 55 is connected to the valve casing IS in opposite relation to the try cock 2!. The elbow 56 is connected to the elbow for a slight swivel motion. Interconnecting the elbows 56 and 51 is a vertical nipple 58, and the elbow 51 having a slight swiveling motion with the means 53 to which it is connected. Hence in addition to the adjust- 55 by rotation of the electrode.

ment above mentioned, a second adjustment is possible, in that the. means 53 may be set at an angle to the vertical for a desired purpose, as will be clear hereinafter, and both adjustments may be practised at the same time. For example, if the device 53 includes a pair of vertically spaced indicators, these may be vertically set relatively to each other.

The control means 53 may include one or more vertically spaced control devices 59, 60 which may be duplicates of each other, and are disposed above and below the normal liquid level in the boiler.

a constricted passage 63 connected to the elbow 51 in alined relation. 1

Interconnecting the chambers 62 of the casing sections 6| is a passage 12, which thus forms a'n H with said chambers. Communicating with the passage 12 as at 13 is a try cock or blow oil valve 14 which may be exactly like those shown at 2 I, and the casing of which may be an integral part of or union connected with the casing 6Ia if desired.

In Fig. 3 is shown a device I09 including an electrode and an improved mounting therefor connected to the casings I8 and GM, asat I6, I! and 59, 60 to afford the control hereinbefore mentioned. The devices I09 are duplicates of each other. Each device may include a bushing I It provided with a central bore III communicating with a packing chamber II2, havinga series of laminated or other packings II3, compressed by a nut Ill. Extending centrally through the bore II I, packing H3 and nut I. is a threaded stem or electrode H5. The latter may be insulated by the packing H3 and by insulator sleeves H6, III, of which the former is retained by the nut II4 acting on the annular flange III! of the sleeve, and the latter by annular end flanges I I9 bent or spun against adjacent opposite surfaces of the bushing. Between the insulator ring H6 and the electrode H is positioned a pliable contact ring I20 retained by an internal annular end flange I2I, and uniformly contacting the electrode under the pressure of the insulation H6, caused especially by the conical opening at Illa in the packingnut II4. A suitable conductor I22 may be connected to an ear or lug I23 of the contact ring. The outer end of the electrode may have a head I24, and the inner end portion thereof may be ta.- pered at I25 and may carry an insulator head I26 for actuating the ball valve 29 wherever the same may be provided. If this electrode is used in the casing section 6|, the head I26may be omitted.

In operation, the electrode II5 forms its own thread in the. packing H3 and may be screwed in and out thereein. The electrode is reliably insulated from all metalic parts, and the connection at I23 is made so that it is not disturbed The latter may be completely removed and reinserted, due to the tapered end, without loosening the nut Ill, and a new thread may be formed- This device will stand up under the highest boiler pressures. The tapered end portion may be readily cleaned in passages 21 and 63, and may adjustably increase the velocity therethrough and even operate as a needle valve therefor.

The electrodes II 5 may be suitably operative to actuate alarm or indicating devices I6, I'I'prei- These control devices may be housed in a one piece casing 6Ia which may have erably so that the devices l6, I1 operate an alarm if the water level becomes too high or too low. Normally, the water level is intermediate of the electrodes of the devices 59, 69, and when the water level rises to the device 59, any suitable means may be caused to shut ofi the feed water. whereas if the water level drops to the device 60, the feed water may be turned on or increased. the operation in each case being caused by the corresponding electrode. Where valves 29 are provided, the electrodes can be directly removed. The cleaning of the electrodes may be ijacilitated by the try cocks 2| and I4 which may also serve to indicate the liquid level. Adequate flushing of the electrodes can be obtained by screwing ,the electrodes inward of the constricand lowered to maintain a desired water level, and also permit these devices to be moved toward and away from each other to vary the range 01' control oi said devices. The electrodes are wholly externally accessible for easy removal, inspection and repair, without requiring expensive means for mounting, sealing and insulating the same.

It will be appreciated that various changes and modifications may be made in the device as shown in the drawing, and that the same is submitted in an illustrative and not in a limiting sense, the scope of the invention being defined in the following claims.

I claim:

1. In a liquid level control for boilers, a casing, a valve therein automatically movable into closed position, a free ended electrode in the casing separate of the valve and having at an end thereof -a portion of electric insulating material, said electrode being movable relative to the casing to cause said portion to open the valve, electrical insulating packing between the electrode and easing, said electrode having threaded enegagement with the packing ior movement of the electrode.

2. In a water level control for boilers, a casing member having a recess, a passage communicating therewith, an electrode extending through the recess and passage, pliable electrical insulating packing in the recess, said electrode being threaded and having snug fitting screw engagement with said packing so as to be out of contact with the casing member, an insulator sleeve in said passage freely disposed about the electrode, and a gland element for compressing the packing with the electrode extending through the gland element, and insulator means between the electrode and the gland element, and the electrode being thresdedly axially adjustable.

3. In a water level control, an electrode, a casing element having a passage for receiving the electrode, said casing element having a recess in communication with said passage, pliable electrical insulating. packing in said recess, a gland element for compressing said packing and being insulated from the electrode, the latter having an external thread for screw engagement with the packing and being spaced from the casing element, and said packing being pressed by said gland into liquid tight engagement with the electrode.

4. A liquid level control, a casing element, an electrode having a threaded shank, said element having a recess and a passage alined therewith, said shank extending through said recess and possage, electrical insulating means including a sleeve, a pliable packing, and a ring, said sleeve freely receiving the electrode and being fitted in said passage, said sleeve having a flange portion secured in the recess, said packing being in the recess and extending around said shank, a gland compressing said packing into liquid tight screw engagement with the electrode shank, the latter being wholly out of contact with the casing element, said gland having a hole for receiving the shank, a conductor member having wiping contact with the shank, and said ring extending around the shank and overlying the conductor to retain the same in position, with said gland bearing on the said ring.

5. In a liquid level control, an electrode having an elongated threaded shank, and means for sealingly mounting the same including a casing element and initially unthreaded pliable electrical insulating packing therein through which said shank extends, and means to compress the packing uniformly about the shank and in engagement with the thread thereof to provide a screw threaded connection between the electrode and the packing for sealing the electrode tight under high pressures and in spaced relation to the casing element.

6. In a liquid level control, an electrode having an elongated threaded shank, and means for sealingly mounting the same including a casing element and initially unthreaded pliable electrical insulating packing therein through which said shank extends, and means to compress the packing uniformly about the shank and in engagement with the thread thereof to provide a screw threaded connection between the electrode and the packing for sealing the electrode tight under high pressures and in spaced relation to the casing element, and said electrode having a tapered end adapted for easy initial insertion into the packing.

7. In a liquid level control, an electrode having an elongated threaded shank, and means for sealingly mounting the same including a casing element and initially unthreaded pliable electrical insulating packing therein through which said shank extends, and means to compress the packing uniformly about the shank and in engagement with the thread thereof to provide a screw threaded connection between the electrode and the packing for sealing the electrode tight under high pressures and in spaced relation to the casing element, and said electrode having at an end thereof a portion consisting of electrical insulating material, said end portion being adapted for actuation of a valve element by screw adjustment of the electrode in said packing.

8. In a liquid level control, an electrode having an elongated threaded shank, and means for sealingly mounting the same including a casing element and initially unthreaded pliable electrical insulating packing therein through which said shank extends, and means to compress the packing uniformly about the shank and in engagement with the thread thereof to provide a screw threaded connection between the electrode and the packing for sealing the electrode tight under high pressures and in spaced relation to the casing element, and a valve separate of and movable by the electrode on screw actuation of the latter along said packing.

9. In a liquid level control, an electrode having an elongated threaded shank, and means for sealingly mounting the same including a casing element and initially unthreaded pliable electrical insulating packing therein through which said shank extends, and means to compress the packing uniformly about the shank and in engagement with the thread thereof to provide a screw threaded connection between the electrode and the packing for sealing the electrode tight under high pressures and in spaced relation to the casing element, and said casing element including a fluid passage having a constricted orifice portion into an entrance of which an end of the electrode adjustably axially extends to a degree determined by screw actuation of the electrode with respect to the packing, whereby the said end of the electrode can be cleaned by said fluid.

GEORGE ERNST. 

